In a nail magazine of a nailing machine, using connected nails referred to as stick nails or sheet nails or the like in which a number of nails are connected by a strip of hard paper or the like, a series charging type nail magazine for increasing a number of charged containing nails by enabling to overlappingly charge a plurality of sheets of connected nails is proposed. A nail magazine of this kind is constituted such that a plurality of sheets of connected nails which are overlappingly charged are pressed to a nail guide face by a pressure plate and nails are fed by a feed claw arranged on a side of the nail guide face.
For example, the nail magazine of two sheets containing type is formed such that when a first row (a first sheet) of connected nails are fed by the feed claw, a second row (a second sheet) of connected nails cannot be moved forward by being brought into contact with a front wall face of a nail containing chamber and only the first row of connected nails disposed at a nail path to a nose are fed. Nail feeding is carried out by a nail feeding air cylinder of a spring offset type, similar to a general nail magazine, a piston is moved rearward by pressurized air supplied from a blowback chamber of a nailing machine and the piston is moved forward by exhausting pressurized air. When the piston is moved forward, the feed claw of a ratchet type attached to a front end of a piston rod is engaged with the first row of connected nails to feed forward, thereby a front nail is fed into the nose. When a tail of the first row of connected nails is moved forward from a front of the second row of connected nails and a space at a position of the first row is vacated, the second row of connected nails are moved to the position of the first row by being pressed by the pressure plate and brought into contact with the tail of the first row of connected nails to continuously supply to the nose.
According to the series charging type nail magazine of the related art, the feed claw is designed to carry out nail feeding by being engaged with only connected nails at the position of the first row. However, when a rearmost nail of the first row passes a position of a front of the second row and the second row of connected nails are moved to the position of the first row, there is a case in which the feed claw is caught by both of the final nail of the first row and the front nail of the second row. The nail path reaching the nose of the striker is provided with a cross width of a single piece of nail and therefore, two pieces of nails which are aligned crossly cannot simultaneously enter the nail path and when the above-described state is produced, nail clogging is brought about to stop nail feeding and connected nails are obliged to recharge.
Further, in the case of the series charging type nail magazine for pressing connected nails constituted by overlappingly containing a plurality of sheets of connected nails to the nail guide face by the pressure plate and feeding nails by the feed claw on the side of the nail guide face, there poses a problem that when a number of sheets of connected nails at inside of the nail magazine becomes single and the connected nails are consumed to some degree, in the case in which a second sheet of connected nails are inserted from a charge port at a rear portion of the nail magazine, also the connected nails enter the position of the first row by being pressed by the pressure plate and butted to the tail of the first row of connected nails and cannot be charged to the side of the first row.
Further, there is also proposed a series type nail magazine constituted by mounting heads of a succeeding row of connected nails above heads of the first row of connected nails to contain at a different stage. According to the series mounting type nail magazine, connected nails at inside of a nail magazine are pressed to a side of a first row by a pressure plate.
When the first row of connected nails are fed by a feed claw in accordance with nail striking operation and a final nail is moved frontward from a front nail of a succeeding row, the succeeding row of nails are pressed by the pressure plate to move to the position of the first row. At this occasion, in order to enable to move succeeding connected nails held at a position higher than that of the first row of connected nails to a slightly lower predetermined position and addingly charge new connected nails contiguous thereto, a ceiling face of a front portion of a guide groove supporting nail heads of the first row of connected nails are inclined downwardly relative to a nail feeding direction and when connected nails moved to the first row are fed frontward by the feed claw, and the nail heads are brought into contact with the ceiling face to move downward forcibly. In this case, in the case of sheet type connected nails N in an inclined shape in which heights of nails are successively lowered to a front side as shown by FIG. 12, when a feed claw 221 moving forward by an angle the same as an inclined angle of the connected nails N presses the connected nails N in a front skewed direction, a vector of the feed claw 221 and an axis of the nail are not orthogonal to each other and therefore, a slippage is produced between the feed claw 221 and the nail and the connected nails N are pressed up in an upward direction. Thereby, the nail head is pressed to a lower inclined face 222 of the ceiling face of the guide groove and cannot smoothly be moved forward and nail feeding may be stopped. Further, by stopping to feed the nail, there is also a possibility that a driver 223 idly strikes a struck member to damage the member and by idle striking, there is concern that an excessive load is applied to the driver or a bumper (impact damping member) to destruct the member. Further, since the nail head portion is pressed to the lower inclined face 222 of the ceiling face of the guide and the front nail is fed by the feed claw 221, at a connecting strip comprising paper, an adhering layer and the like having a low nail holding force, there is also a possibility that the front nail is detached from the connecting member before being struck to thereby cause a clogging.
It is an object of the invention to resolve instability in nail feeding in a series charging type nail magazine.
Further, it is an object of the invention to enable to charge connected nails to predetermined positions firmly and easily.